Zara Tindall, the Duke of Cambridge's cousin, is the only member of the royal family named as a godparent to Prince George, Kensington Palace has announced.

She is one of seven godparents chosen by the Duke and Duchess, joining old friends from their school and university days, as well as members of the aristocracy, on the list.

A close friend of Diana, Princess of Wales has also been chosen as a godparent for today's service at the Chapel Royal in St James's Palace, where the Princess lay at rest before her funeral in 1997.

Jamie Lowther-Pinkerton (left) the Duke and Duchess's principal private secretary and William van Cutsem, one of the Duke's oldest friends (REX)

Among the more predictable names on the list are Jamie Lowther-Pinkerton, the Duke and Duchess's principal private secretary, who has worked for the Duke since 2005, and William van Cutsem, one of the Duke's oldest friends.

Melissa Nicholson and Oliver Baker (left) and Emilia and David Jardine-Paterson (Rex)

The other names on the list, however, were not widely predicted. They are Oliver Baker, a friend of the Duke and Duchess who was at St Andrews University with them, Emilia Jardine-Paterson, who was at Marlborough College with the Duchess, Earl Grosvenor, the son of the Duke of Westminster, and The Hon Julia Samuel, who was a close friend of the Princess of Wales.

The Duke of Cambridge with Julia Samuel (David Bebber/The Times/PA)

Just 22 guests will be at the intimate service - the godparents and six spouses (Earl Grosvenor is not married), the Duchess's parents and two siblings Pippa and James, and the Queen, Duke of Edinburgh, Prince of Wales, Duchess of Cornwall and Prince Harry.

Prince George will wear a handmade replica of the Honiton lace royal christening robe, the original of which dates back to Victorian times, and will be baptised with water from the River Jordan in the Lily Font at the Chapel Royal.

The interior of the Chapel Royal at St James's Palace in central London, where Prince George of Cambridge will be christened (PA)

Following the service, which will be conducted by the Archbishop of Canterbury, the Prince of Wales and the Duchess of Cornwall will give a private tea in Clarence House where guests will be served slices of the christening cake, which is a tier taken from the Duke and Duchess's wedding cake.

Official pictures by the photographer Jason Bell will be taken in Clarence House and released to the media on Thursday night.